function p_ = quickTA_val(cohs, times, r, beta, lambda)% function p_ = quickTA_val(cohs, times, r, beta, lambda)%%   Computes a Quick (Weibull) function derived explicitly% Assuming temporal accumulation (TA) of a constant% stimulus (coherence). In this model, we assume there is a single% channel whose response is given by r*time. Thus, the "vector magnitude"% ||R|| described by Quick (1974) is also just r*time, which implies% that the threshold (alpha), which is just ||R||^-1, becomes% alpha = 1/(r*time)%% lambda is the lapse rate. Assumes a guess rate (gamma) of 0.5p_ = 0.5 + (0.5 - lambda) * (1 - exp( -(times.*cohs.*r).^beta));